1. Field of Invention
The invention relates to a sewing cartridge to be used by attaching to a sewing apparatus, more particularly, to a sewing cartridge provided with a sewing needle and a guard member that guards at least a tip of the needle.
2. Description of Related Art
Conventionally, a sewing apparatus, such as a sewing machine, performs sewing on a work cloth using upper and lower threads in cooperation with a thread take-up, a thread loop taker and a needle. The needle is threaded with the upper thread and moves vertically. A general home sewing machine performs sewing using a single needle attached to a lower end of a needle rod. Accordingly, when the upper thread wound around a spool runs out or when an upper thread needs to be changed to sew a different color of a color pattern, after the spool for the upper thread is changed, the upper thread is threaded to a predetermined guide portion provided on the sewing machine and then needs to be threaded through a needle hole.
A conventional sewing apparatus and sewing cartridge, that can be attached to and detached from the sewing apparatus, including the sewing cartridge accommodating a needle and a spool therein, wherein threading of an upper thread and threading of an upper thread through a needle hole can be omitted when an upper thread wound around a spool runs out or when an upper thread needs to be changed to sew a color pattern, is disclosed in U.S. Pat. No. 4,100,867, the disclosure of which is incorporated herein by reference.
The needle attached to the sewing cartridge is similar to a general sewing a thread is threaded through a needle hole at its lower end. When the sewing cartridge is attached to the sewing apparatus, the needle and a needle up and down mechanism, provided to the sewing apparatus, are connected to each other to move integrally. As a machine motor is driven, the needle is moved up and down by the needle up and down driving mechanism with respect to the sewing cartridge fixed to the main body of the sewing machine. Thus, the operation in which the needle passes through a work cloth is repeated, whereby sewing is performed on a work cloth using an upper thread and a looper member.
In a conventional general home sewing machine, the needle that moves vertically is exposed, so that the needle may catch clothes or other objects and be damaged. Every time, when the upper thread wound around a spool runs out or when an upper thread needs to be changed to sew a different color of a color pattern, the troublesome operation such that the upper thread is threaded to a predetermined guide portion provided on the sewing machine and then threaded through a needle hole needs to be performed. Accordingly, the sewing machine cannot be easily handled.
In the sewing apparatus disclosed in U.S. Pat. No. 4,100,867, the needle is moved up and down with respect to the sewing cartridge when the sewing cartridge is attached to the sewing machine. Therefore, the structure of the sewing cartridge becomes complicated. Further, the sewing apparatus needs to be provided with the needle up and down driving mechanism, having a relatively complicated structure, that moves the needle in the sewing cartridge up and down. Accordingly, manufacturing costs of the sewing apparatus become high and it becomes difficult to reduce the size and the weight of the sewing apparatus.
In such a sewing cartridge, the needle extends from the sewing cartridge and into a work cloth. If the sewing cartridge is removed while the needle is protruding from the sewing cartridge, the sewing cartridge needs to be handled with care. In the sewing apparatus disclosed in U.S. Pat. No. 4,100,867, such a situation is prevented from occurring as the power of a drive circuit of the machine motor that moves the needle up and down can only turn off when the needle retracts into the cover.
In the conventional sewing apparatus, the needle used is a general sewing needle having a thread threaded through the needle hole at its lower end. Therefore, it is difficult to form a pattern unless the needle cooperates with a thread take-up and a thread loop taker. That is, a driving mechanism that drives the thread take-up and the thread loop taker is needed. Accordingly, it is extremely difficult to reduce the size and the weight of the sewing apparatus.
U.S. Pat. No. 3,749,039 discloses a sewing apparatus, including a sewing cartridge accommodating a spool therein, that automatically threads an upper thread, extending from the spool, in the sewing cartridge onto a thread tensioning member provided to a sewing apparatus body when the sewing cartridge is attached to the sewing apparatus body. In this sewing apparatus, a sewing needle is not provided to the sewing cartridge, but to the sewing apparatus body. Therefore, when the sewing cartridge is attached to or detached from the sewing apparatus, to change or refill the thread, care should be taken with respect to the tip of the sewing needle, attached to the sewing apparatus body, to perform the operations safely, as is the case of the general sewing machine. The disclosure of the sewing apparatus in U.S. Pat. No. 3,749,039 is herein incorporated by reference.
The invention provides to a sewing cartridge that improves safety while simplifying the operation of changing an upper thread in a sewing apparatus.
According to one aspect of the invention, a sewing cartridge detachably attached to a sewing apparatus that performs sewing on a workpiece includes a needle for sewing and a guard member that guards at least a tip of the needle.
With this structure, sewing can be performed by attaching the sewing cartridge to a sewing apparatus. By changing the sewing cartridge, the thread can be changed to another thread in the sewing apparatus. Accordingly, it is extremely easy to perform operations, such as changing or refilling the thread. Further, the sewing cartridge includes the guard member that guards at least the tip of the needle. Accordingly, the sewing cartridge can be handled with safety both when the sewing cartridge is being attached to the sewing apparatus and when the sewing cartridge is removed from the sewing apparatus. Further, damage to the needle can be avoided.